This is an observational retrospective cohort in real world to describe RAL data, including NUC-sparing regimens, in aged HIV patients. It is a phase IV study. 90 patients will be enrolled from the Department of Public Health and Infectious Diseases of "Sapienza" University of Rome. More than 4000 HIV patients are followed at this Department of Public Health and Infectious Diseases of "Sapienza" University of Rome. More than 50% of these patients are ≥ 50 years. From 10 to 12% are treated with a raltegravir based- regimen.